February 26-28, 2019

Dr. Todd McAlary has a Bachelor’s degree in Geological Engineering, a Master’s degree in Hydrogeology and a Ph.D. In Chemistry, all from the University of Waterloo. He has 30 years of environmental consulting experience and has worked on projects across North America, mostly for large multinational private companies and the United States Department of Defence. He has been the Vapor Intrusion Practice Leader at Geosyntec Consultants, Inc. for 18 years. He has authored or co-authored about a dozen guidance documents for vapor intrusion assessment and mitigation, has several peer-reviewed journal articles and is co-inventor on a patent related to quantitative passive soil vapor sampling. He is also an Adjunct Professor at the University of Toronto, Department of Chemical Engineering.

SESSION KEYNOTE PRESENTER – Vapor Intrusion: Don't Hold Your Breath

Better Mousetraps for Vapor Intrusion

Vapor Intrusion assessment and mitigation faces several common challenges, including temporal variability, spatial variability, background sources, very low screening levels and site-specific conditions. AS a result, the routine methods of assessment described in most regulatory guidance documents often result in ambiguous outcomes, or and unknown risk of false-positive and false-negative results. Applied research conducted over the past decade has identified several alternatives to the conventional assessment techniques that can provide data with less variability, resolution of background sources and significantly reduce the uncertainty in assessment. Several different approaches for mitigation are also being developed and demonstrated/validated. Collectively, these emerging methods can dramatically improve the timeliness, cost and certainty of vapor intrusion assessment and mitigation, but the selection and application of the lines of evidence is more complex and regulatory approval often requires some additional effort. This talk will cover a broad cross section of options with a focus on the site-specific conditions that influence the selection of the most valuable alternatives.